Older people of Mexican origin make up one of the fastest -growing segments of the U.S. population, and their numbers are projected to increase sevenfold by 2050. This demographic explosion will place serious demands on the long-term care system, from family caregivers to federally sponsored sources of care. Mexican Americans suffer disproportionately from disabling conditions like diabetes that increase their risk of care in a nursing home or assisted-living facility. The relationship between functional decline and subsequent institutionalization for this population, however, may be largely influenced by a combination of factors, including economic resources and family and social support network. These factors may, in turn, vary by nativity, age at migration, and acculturation. To date, few studies have tested predictive models on how immigration-related factors, economic resources, and family support converge to determine care and living arrangements (i.e., living alone, living with spouse or family, or institutionalization) in elderly Mexican-origin individuals with declining functional status. The overall goal of this study is to clarify the most important factors associated with changes in the care and living arrangements of elderly Mexican Americans. We will evaluate a new empirical model to determine how immigration factors (e.g., nativity, age at migration, acculturation) and family resources (e.g., financial security, family and social support network) moderate how changes in functional status induce changes in care and living arrangements among older Mexican Americans in the United States. The specific aims are to: (1) examine the physical and cognitive functioning trajectories of elderly Mexican Americans between 1993 and 2008, by immigration factors;(2) assess how declines in functional status of elderly Mexican Americans relate to changes in care and living arrangements, by immigration factors;and (3) estimate the joint effect of family resources and immigration factors on use of nursing homes and assisted- living facilities by elderly Mexican Americans. We will use standard demographic and epidemiological techniques to analyze 3,952 individuals included in the Hispanic Established Populations for Epidemiologic Study of the Elderly (H-EPESE), the largest and most representative survey on the longitudinal health of older Mexican Americans. The results will identify key predictors of Mexican Americans'care and living arrangements, including the use of nursing homes and assisted-living facilities, providing important insights into social processes that will affect all aging families in the future. The study will also inform policy makers and best practice models in reducing disparities in unmet long-term care service needs. PUBLIC HEALTH RELEVANCE: PROJECT NARRATIVE This research will provide invaluable information regarding long-term care for the older Hispanic population in the United States, and specifically the region closest to Mexico, the Southwestern United States, which suffers greatly on most socioeconomic indicators. For cultural reasons, Mexican Americans are much less likely to use formal institutional care as they become infirm with age, regardless of the level of their disability. Traditionally they rely on family for their care which thereby creates a potential dependency burden on these caregivers and social agencies. The ultimate goal of the research is to identify mechanisms for reducing disparities in options in long-term care.